This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This vaccine study will test several DC-targeting vehicles for their ability to elicit potent protective immunity against influenza virus infection. Antibody-mediated immunity is an important immune arm for the prevention of influenza infection. To evaluate the potency of DC-targeting vaccines administered i.d., we employ a current vaccine, Fluzone, as a positive control. Although the main objective of this study is to test HA1-specific humoral responses, we will also test the magnitude and spectrum of HA1-specific cellular responses that are necessary for eliciting potent humoral immunity.